IN THE UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

ASSOCIATION OF IRRITATED

RESIDENTS, et al.,

Petitioners, 

v. 

UNITED STATES ENVIRONMENTAL 

PROTECTION AGENCY, et al.,

Respondents. 

Nos. 09-71383 and 09-71404

(Consolidated) 

On Petitions for Review of Final Action of the

United States Environmental Protection Agency

PETITION FOR PANEL REHEARING

Of Counsel: IGNACIA S. MORENO

JEFFERSON L. WEHLING Assistant Attorney General

U.S. EPA Region IX Environment & Natural Resources Division

Office of Regional Counsel

75 Hawthorne St. AUSTIN D. SAYLOR

San Francisco, CA 94105 United States Department of Justice

Environmental Defense Section

JAN M. TIERNEY P.O. Box 23986

MICHAEL W. THRIFT Washington, D.C. 20026-3986

U.S. EPA

Office of General Counsel

1200 Penn. Ave. NW MC2344A

Washington D.C. 20460

May 5, 2011

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TABLE OF CONTENTS

BACKGROUND .........................................................................................................2

I. STATUTORY BACKGROUND ......................................................................2

A. Select State Implementation Plan Requirements in “Extreme” 

Nonattainment Areas...............................................................................2

B. Federal Implementation Plans and Sanctions .........................................3

C. The 2003 State Strategy and 2003 South Coast Air Quality 

Management Plan....................................................................................4

II. PETITIONERS’ ARGUMENTS AND THE COURT’S DECISION..............5

ARGUMENT...............................................................................................................7

I. THE COURT ERRONEOUSLY CONCLUDED THAT EPA’S 

DISAPPROVAL OF THE 2003 ATTAINMENT DEMONSTRATION 

TRIGGERED SANCTIONS UNDER SECTION 7509 

OF THE ACT ....................................................................................................7

II. THE COURT ERRED IN FAILING TO DEFER TO EPA’S 

REASONABLE INTERPRETATION OF THE AMBIGUOUS 

STATUTORY REFERENCE TO “GROWTH IN EMISSIONS” ...................11

CONCLUSION............................................................................................................18

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TABLE OF AUTHORITIES

CASES

Association of Irritated Residents, et al. v. EPA, 

632 F.3d 584 (9th Cir. 2011)........................................................................ passim

BedRoc Ltd. v. United States, 

541 U.S. 176 (2004) .............................................................................................17

California Wilderness Coalition v. U.S. Department of Energy, 

631 F.3d 1072 (9th Cir. 2011)..............................................................................11

Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 

467 U.S. 837 (1984) .............................................................................................11

Davis v. Michigan Dep't of Treasury, 

489 U.S. 803 (1989) .............................................................................................15

Field v. Mans, 

516 U.S. 59 (1995) ...............................................................................................10

United States v. Daas, 

198 F.3d 1167 (9th Cir. 1999)..............................................................................15

STATUTES

42 U.S.C. § 7410(c)(1)(A)-(B) ..................................................................................4

42 U.S.C. § 7410(k)(5)...............................................................................................8

42 U.S.C. § 7502(c)(3)................................................................................ 3, 8, 9, 10

42 U.S.C. § 7506(c)(1)................................................................................ 3, 8, 9, 10

42 U.S.C. § 7506(c)(1)(B) .........................................................................................7

42 U.S.C. § 7509(a) ...............................................................................................4, 8

42 U.S.C. § 7509(a)(1)-(4).........................................................................................4

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42 U.S.C. § 7509(b)(1)-(2) ........................................................................................4

42 U.S.C. § 7511a(c)(2).............................................................................................9

42 U.S.C. § 7511a(c)(2)(A) .......................................................................................2

42 U.S.C. § 7511a(d)(1)(A).................................................................. 3, 5, 6, 12, 17

42 U.S.C. § 7511a(e)..................................................................................................2

FEDERAL RULES OF APPELLATE PROCEDURE

Fed. R. App. P. 40(a)(2).............................................................................................1

FEDERAL REGISTER

56 Fed. Reg. 56,694 (Nov. 6, 1991)...........................................................................2

74 Fed. Reg. 10,176 (March 10, 2009)......................................................................5

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Pursuant to Rule 40 of the Federal Rules of Appellate Procedure and the 

associated rules of this Court, Respondent United States Environmental Protection 

Agency (“EPA”) respectfully requests panel rehearing of certain aspects of the

Court’s decision in Association of Irritated Residents, et al. v. EPA, 632 F.3d 584 

(9th Cir. 2011) (slip opinion attached hereto). 

EPA believes the Court “overlooked or misapprehended” two important 

points of law, see Fed. R. App. P. 40(a)(2), resulting in erroneous holdings 

regarding the imposition of sanctions under section 7509(a)(2) of the Clean Air 

Act (“the Act”)1

 1 Except as otherwise noted, statutory references are to Title 42 of the United States 

Code.

and the circumstances under which an area must adopt 

transportation control measures pursuant to section 7511a(d)(1)(A) to offset 

increases in vehicle emissions. First, in holding that EPA had a duty to impose 

sanctions under section 7509(a)(2) when EPA disapproved California’s 

voluntarily-revised attainment demonstration, the Court overlooked the fact that 

section 7509(a)(2) on its face applies only to “required” state implementation plan 

(“SIP”) submissions and not to voluntary submissions. Second, in holding that the 

Los Angeles-South Coast Air Basin Area (“South Coast”) was unambiguously 

required under section 7511a(d)(1)(A) to implement transportation control 

measures even though aggregate vehicle emissions were decreasing, the Court

failed to recognize, or defer to EPA’s reasonable interpretation of, the ambiguity 

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inherent in the section’s reference to a “growth in emissions.” The Court’s 

erroneous holdings on these issues have profoundly costly and disruptive 

implications for EPA, States, and localities across the nation, and likely will 

discourage States and localities from updating their Clean Air Act implementation 

plans except when absolutely required to do so by the Act.

BACKGROUND

I. STATUTORY BACKGROUND

A. Select State Implementation Plan Requirements in “Extreme” 

Nonattainment Areas

As noted in earlier briefing in this case, the South Coast is designated 

“nonattainment” for the national ambient air quality standard (“NAAQS”) for 1-

hour ozone, and EPA has classified the South Coast ozone nonattainment area as 

“extreme” for 1-hour ozone, with an attainment deadline of November 15, 2010. 

See 56 Fed. Reg. 56,694, 56,726 (Nov. 6, 1991). 

“Extreme” ozone nonattainment areas such as the South Coast are subject to 

stringent requirements under the Act. Such areas were required to submit, within 

four years of enactment of the November 1990 CAA Amendments, a 

demonstration that the area’s SIP provides for attainment of the ozone NAAQS by 

the applicable deadline. 42 U.S.C. § 7511a(c)(2)(A); id. § 7511a(e). This socalled “attainment demonstration” includes both a control strategy and air quality 

modeling showing that the control strategy is sufficient to reduce emissions to 

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levels where violations of the NAAQS would not occur by the attainment date. 

Extreme nonattainment areas must also adopt transportation control measures and 

strategies “to offset any growth in emissions from growth in vehicle miles 

traveled,” and “to attain reduction in motor vehicle emissions as necessary, . . . to 

comply with the requirements of . . . this section (pertaining to periodic emissions 

reduction requirements).” Id. § 7511a(d)(1)(A).

Section 7506(c) of the Act provides that before any transportation program 

or project located in a nonattainment area can receive federal approval or funding, 

that transportation activity must be found to “conform” with the applicable SIP. 

An activity “conforms” to an approved SIP if, based on the most recent estimates 

available, the anticipated emissions will not (1) frustrate the general purpose of the 

SIP; (2) cause or contribute to a new violation of the NAAQS; (3) worsen an 

existing violation; or (4) delay timely attainment of a NAAQS or other milestone. 

Id. § 7506(c)(1). 

B. Federal Implementation Plans and Sanctions

If a State fails to submit a SIP or EPA disapproves a SIP, in many instances 

EPA is required to promulgate a federal implementation plan (“FIP”) and to 

impose mandatory sanctions. The Act requires EPA to promulgate a FIP within 

two years after the Administrator either “finds that a State has failed to make a 

required submission or finds that the plan or plan revision” is incomplete, or 

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“disapproves a [SIP] in whole or in part.” Id. § 7410(c)(1)(A)–(B). EPA is no 

longer required to promulgate a FIP if “the State corrects the deficiency, and the 

Administrator approves the plan or plan revision, before the Administrator 

promulgates such federal implementation plan.” Id. 

Certain mandatory sanctions set forth in section 7509(b) apply2

C. The 2003 State Strategy and 2003 South Coast Air Quality 

Management Plan

when EPA 

makes any one of four findings regarding “any implementation plan or plan 

revision required under this part (or required in response to a finding of substantial 

inadequacy as described in section 7410(k)(5) of this title).” Id. § 7509(a). The 

four findings are: a failure to submit the plan; a determination that a submitted 

plan is incomplete; a disapproval of a submitted plan; or a determination that a 

state is not implementing an approved plan. Id. § 7509(a)(1)–(4). 

On January 9, 2004, the California Air Resources Board (“CARB”) 

submitted to EPA two SIP revisions related to the 1-hour ozone standard: a plan 

identifying CARB’s regulatory agenda to reduce ozone in all areas of California by 

2010 (“2003 State Strategy”), and the 2003 South Coast Air Quality Management 

Plan (“AQMP”). The 2003 South Coast AQMP was submitted by the State in light 

of new photochemical modeling performed by the South Coast Air Quality 

 2 These sanctions include prohibitions on new highway projects or grants, and 

limitations on new construction or modification of major stationary sources of air 

pollution. Id. § 7509(b)(1)–(2).

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Management District purporting to show the need for additional emissions 

reductions, and to establish new motor vehicle emissions budgets and thereby 

avoid a transportation conformity lapse and associated federal funding losses. 

On March 10, 2009, EPA disapproved the revised attainment demonstration 

because of its reliance on various state commitments originally included in the 

2003 State Strategy, but withdrawn by CARB before EPA acted on the submission. 

74 Fed. Reg. 10,176 (Mar. 10, 2009). EPA concluded that its disapproval of the 

revised attainment demonstration did not trigger mandatory sanctions under section 

7509, because the State already had in place a plan that EPA had fully approved as 

meeting the attainment demonstration obligation under section 7511a(c) and (e), 

and the revised attainment demonstration was not an implementation plan 

“required” under the Act. Id. at 10,177. EPA approved the State’s demonstration 

that aggregate vehicle emissions would decline each year from the base year of the 

plan through the attainment year of 2010. Absent a “growth in [aggregate] 

emissions” from motor vehicles, EPA concluded that no transportation control 

measures were required under section 7511a(d)(1)(A). Id. at 10,179.

II. PETITIONERS’ ARGUMENTS AND THE COURT’S DECISION

Petitioners challenged several aspects of EPA’s March 10, 2009 final rule.

Relevant to this petition for rehearing, Petitioners argued that upon disapproving 

the State’s revised attainment demonstration for the 1-hour ozone standard, EPA 

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should have required California to submit a new plan demonstrating attainment,

notwithstanding that a previously-approved attainment demonstration remained on 

the books. Petitioners also claimed that EPA acted contrary to section 

7511a(d)(1)(A) of the Act by not requiring the State to adopt transportation control

measures where vehicle emissions were higher than they would have been had 

vehicle miles traveled not increased, but, in fact, total vehicle emissions were 

declining.3

On the first issue, the Court held that in light of EPA’s disapproval of the 

revised attainment demonstration, it must either “promulgat[e] a FIP, issu[e]

sanctions, or evaluat[e] the necessity of a SIP call.” 632 F.3d at 594. On the 

second issue, the Court held that EPA should have required California to adopt 

transportation control measures and strategies pursuant to section 7511a(d)(1)(A)

because the State projected that vehicle miles traveled would increase in the region 

through 2010, and the Court read the statute as unambiguously providing that a

“growth in emissions” caused by an increase in vehicle miles traveled results 

 3 That aggregate vehicle emissions could decrease even though vehicle miles 

traveled increase is not as strange as it might sound; indeed, it could well be 

expected. It could, for instance, occur where there are more cars on the road than 

there were before due to an increase in population, but those cars on average are 

cleaner-burning, due to the natural replacement of older more polluting models 

with newer models (including hybrid or electric vehicles). In such a case, emission

levels would be higher than they would have been had vehicle miles traveled not 

increased, but those emission levels could still be lower than previous levels based 

on prior vehicle miles traveled, offset by the overall emission reductions resulting

from the introduction of the less-polluting new cars or use of cleaner fuels. 

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whenever vehicle emissions levels are greater than they would have been had 

vehicle miles not increased at all, even if overall vehicle emissions are decreasing. 

Id. at 595. 

ARGUMENT

I. THE COURT ERRONEOUSLY CONCLUDED THAT EPA’S 

DISAPPROVAL OF THE 2003 ATTAINMENT DEMONSTRATION 

TRIGGERED SANCTIONS UNDER SECTION 7509 OF THE ACT

EPA’s disapproval of the State’s revised attainment demonstration did not 

trigger sanctions under section 7509(a), because the States’ attainment 

demonstration was not “required” under the Act. Respectfully, the Court’s 

statements to the contrary are in error.

The Court held that EPA’s disapproval of the State’s revised attainment 

demonstration triggered the requirement of section 7410(c)(1)(B), for EPA to 

promulgate a FIP unless the State corrected the deficiency within two years, 

although the Court left open the possibility that “EPA can find that the state has 

‘corrected the deficiency’” if EPA evaluates the existing SIP and finds that it 

continues to meet the Act’s requirements. 632 F.3d at 592. The Court determined 

that the FIP provision of section 7410(c)(1)(B) is not on its face limited to

situations in which EPA disapproves a “required” submission, and, in any event, 

held that the revised attainment demonstration submitted by the State was 

“required.” Id. The Court further determined, without analysis, that the sanctions 

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requirement at section 7509 was similarly triggered by EPA’s disapproval of the 

revised attainment demonstration. Id. The sanctions provision, however, unlike 

the FIP provision, is expressly limited to “required” submissions. 42 U.S.C. § 

7509(a) (“[f]or any implementation plan or plan revision required under this part . . 

. .”) (emphasis added). Thus, whether sanctions were triggered by EPA’s 

disapproval hinges on whether the revised attainment demonstration was indeed a

“required” submission. As explained below, the revision was not “required.”

The Court stated that “large portions of the 2003 Attainment Plan were not 

discretionary.” 632 F.3d at 592. In support, the Court pointed to the updated 

emissions inventory required by sections 7502(c)(3) and 7511a(a)(3)(A), and the 

fact that the State chose to submit updated motor vehicle emissions budgets to 

avoid a lapse in federal transportation funding, see 42 U.S.C. § 7506(c)(1). 

Neither of those provisions, however, establishes that the attainment demonstration 

was “required” under the Act. The Act does not require or provide for revisions to 

attainment demonstrations absent certain findings that EPA has not made with 

respect to the 1-hour ozone standard in the South Coast.4

 4 For example, a new attainment demonstration is required where EPA has made a 

finding under section 7410(k)(5) that the SIP is “substantially inadequate to attain 

or maintain the relevant [NAAQS],” or has made a finding under section 7509(c) 

that an area failed to attain the relevant NAAQS by the applicable attainment date. 

EPA has made no such findings here.

 While States are always

free to submit SIP updates and revisions to EPA, this does not render such 

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submissions “required” under the Act. 

The Court fundamentally erred in relying on the provisions of the Act that 

require nonattainment areas to periodically revise their emissions inventories 

(sections 7502(c)(3) and 7511a(a)(3)(A)) as support for its conclusion that the 

revised attainment demonstration was “required” by the Act. See 632 F.3d at 592. 

The provisions specific to attainment demonstrations, sections 7502(c)(1) and 

7511a(c)(2)(A), contain no such requirement for periodic revisions. Rather, the

attainment demonstration provisions clearly contemplate only a one-time 

submission by the State to meet the statutory obligation. Under section 7502(b), an 

attainment demonstration pursuant to section 7502(c)(1) must be submitted by a 

date established by the Administrator, which can be no later than three years 

following a designation of “nonattainment.”

Similarly, section 7511a(c)(2) requires submission of an attainment 

demonstration within “4 years after November 15, 1990.” Significantly, section 

7511a makes no reference whatsoever to any later attainment demonstrations, and 

the lack of any such reference should have resolved the issue in EPA’s favor. 

Indeed, in determining elsewhere in its opinion that the FIP obligation in section 

7410(c)(1)(B) is not limited to instances in which the State fails to submit, or EPA 

disapproves, a “required” submission, the Court relied heavily on the canon of 

statutory construction that, “when Congress includes particular language in one 

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section of a statute but omits it in another section of the same Act, it is generally 

presumed that Congress acts intentionally and purposely in the disparate inclusion 

or exclusion.” 632 F.3d at 591 (internal quotations and citations omitted). That 

same canon should have led the Court to conclude that no obligation to submit 

additional attainment demonstrations existed here, because Congress expressly 

included no such obligation in the statute, when other sections show that it could 

have done so if it had so intended. In short, the absence of a requirement in section 

7511a to periodically revise the attainment demonstration should be read as a 

purposeful omission by Congress, such that revisions to attainment demonstrations 

are not “required” by the Act. See Field v. Mans, 516 U.S. 59, 66 (1995). 

Similarly, the Panel erred in relying on the conformity provisions of section 

7506(c), which requires that conformity determinations be based on the most 

recent estimates of emissions, as support for its conclusion that portions of the 

2003 attainment plan submission were not discretionary. First, this statutory

requirement applies only to conformity determinations, which are made by federal 

agencies prior to funding or approving transportation plans and projects, and does 

not apply to SIPs (including attainment demonstration SIPs). Nothing in section 

7506(c) requires States to make any adjustments or revisions to SIPs, whether in 

relation to updated emissions estimates or otherwise. As a practical matter, many 

States do elect to revise their SIPs to reflect more recent emissions estimates, as 

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California did in this case, but this practice is voluntary and is not compelled by 

section 7506(c) or by any other provision of the Act. 

EPA’s disapproval of the State’s voluntarily revised 1-hour ozone attainment 

demonstration did not trigger sanctions under section 7509, because on its face that 

provision applies only to “required” submissions. Even if the interplay of the 

relevant statutory provisions were ambiguous, however, the Court should have 

deferred to EPA’s reading of how to harmonize them with one another under 

Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 

842–44 (1984). The Court erred in holding otherwise.

II. THE COURT ERRED IN FAILING TO DEFER TO EPA’S 

REASONABLE INTERPRETATION OF THE AMBIGUOUS 

STATUTORY REFERENCE TO “GROWTH IN EMISSIONS”

A bedrock principle of administrative law is that a court must not substitute 

its own judgment as to the meaning of an ambiguous statutory provision for an

agency’s reasonable interpretation. See Chevron, 467 U.S. at 842–44; California 

Wilderness Coalition v. U.S. Department of Energy, 631 F.3d 1072, 1084 (9th Cir. 

2011). The statutory provision at issue in this case, section 7511a(d)(1)(A), does 

not specify how to calculate a “growth in emissions” from growth in vehicle miles 

traveled or numbers of vehicle trips, because it does not specify whether the term 

“emissions” refers to emissions from motor vehicles in the aggregate or just to 

levels of emissions (whether increasing or decreasing) affected by the increase in 

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vehicle miles traveled or numbers of vehicle trips. The Court impermissibly

resolved this statutory ambiguity by weighing EPA’s interpretation of this 

language against Petitioners’ interpretation, and then adopting Petitioners’. The 

Court’s failure to acknowledge this statutory ambiguity and defer to EPA’s 

reasonable interpretation under Chevron was in error. 

The Court concluded that the following language unambiguously requires 

States to adopt transportation control measures and strategies whenever vehicle 

emissions are projected to be higher than they would have been had vehicle miles 

traveled not increased, even when aggregate vehicle emissions are actually 

decreasing: 

[States must submit a SIP revision] that identifies and adopts specific 

enforceable transportation control strategies and transportation control 

measures to offset any growth in emissions from growth in vehicle 

miles traveled or numbers of vehicle trips in such area and to attain 

reduction in motor vehicle emissions as necessary, in combination 

with other emission reduction requirements of this subpart, to comply 

with the requirements of subsection (b)(2)(B) and (c)(2)(B) of this 

section (pertaining to periodic emissions reduction requirements). 

42 U.S.C. § 7511a(d)(1)(A) (emphasis added); see 632 F.3d at 596. The statute, 

however, does not define what constitutes a “growth in emissions” – how EPA is 

to determine whether, and to what extent, there will be a “growth in emissions” 

caused by a growth in vehicle miles traveled is left utterly unexplained. Chevron

requires the Court to have deferred to EPA’s reasonable interpretation that there is 

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no “growth in emissions” to offset (and transportation control measures are thus 

not required) where a State demonstrates that aggregate vehicle emissions are in 

fact not increasing from prior levels, notwithstanding any growth in vehicle miles 

traveled or numbers of vehicle trips taken. 

The interpretation adopted by the Court, which looks only to whether 

vehicle emissions (even if actually decreasing over time) are higher than they 

would have been had the number of vehicle miles traveled remained constant, is 

not dictated by the plain terms of the statute. Although the Court held that the 

baseline by which to identify a “growth in emissions” “must be viewed as any 

increase in emissions due solely to VMT,” see 632 F.3d at 596 (emphasis added), 

the statute does not on its face mandate that baseline or otherwise compel reading 

“growth” to refer to vehicle emissions that are actually decreasing in the aggregate 

notwithstanding any growth in vehicle miles traveled. Rather, the statute does not 

answer whether there can be a “growth in emissions” where vehicle emissions are 

higher than they would have been if the number of vehicle miles traveled had 

remained constant, but are actually lower than they were before as a result of

cleaner vehicles entering the fleet and other factors that reduce vehicle emissions. 

The Court recognized that there must be “growth” of two distinct elements 

to trigger the transportation control measure requirement – growth in vehicle miles 

traveled and growth in resulting emissions – and that growth in the former does not 

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necessarily represent growth in the latter. See id. at 595. The statute is thus readily 

susceptible to EPA’s longstanding interpretation that there is no “growth in 

emissions” to be offset where aggregate vehicle emissions have actually decreased 

and are projected to continue to decrease. Although the Court purported to adhere 

to Chevron’s “familiar two-step procedure,” id. at 596, it appears to have 

impermissibly resolved statutory ambiguity in favor of what it determined to be its

preferred interpretation. 

The Court’s criticisms of EPA’s interpretation are not accurate. First, the 

Court incorrectly stated that “EPA’s interpretation only gives effect to the second 

clause of the relevant sentence, and not to the first.” 632 F.3d at 596. The Court

stated that EPA’s interpretation addressed the requirement to impose transportation 

control measures as needed “to attain reduction in motor vehicle emissions [to 

comply with periodic emissions reduction requirements],” but not the requirement 

to offset “growth in emissions from growth in vehicle miles traveled.” Id. 596–97. 

To the contrary, EPA has consistently read these two elements as separate, and 

would require adoption of transportation control measures if an increase in vehicle 

miles traveled caused an increase in aggregate vehicle emissions, even if adoption 

of transportation control measures would not be required (under the second clause 

of the provision) because no reduction in motor vehicle emissions would be 

necessary to meet periodic emissions reduction requirements, and vice versa. 

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Indeed, the separate clauses may require different numbers and kinds of offsetting 

transportation control measures, on different implementation schedules. EPA’s 

interpretation is not, as the Court inaccurately stated, redundant.

Second, the Court erred in concluding that legislative history “clearly 

refutes” EPA’s interpretation. 632 F.3d at 597. The proper question is not whether 

legislative history “refutes” EPA’s interpretation, but whether legislative history 

clarifies an otherwise ambiguous statute.5

Under the interpretation adopted by the Court, any level of vehicle 

 In any event, here the legislative history

does neither. While a House Committee Report states that the phrase “growth in 

emissions” should be measured according to “the level of emissions that would 

occur if VMT held constant in the area,” such a baseline conflicts with both the 

plain text of the statute and the Court’s conclusion that there must be growth in 

each of the separate elements (vehicle emissions and vehicle miles traveled) to 

trigger the control requirement. See id. Such an approach essentially reads the 

phrase “growth in emissions” out of the statute, rendering it mere surplusage, as if 

all the Act requires is a simplistic analysis of whether vehicle miles traveled are

increasing. 

 5 “[L]egislative history is irrelevant to the interpretation of an unambiguous 

statute.” Davis v. Michigan Dep’t of Treasury, 489 U.S. 803, 808 n.3 (1989); 

United States v. Daas, 198 F.3d 1167, 1174 (9th Cir. 1999) (“If the statute is 

ambiguous – and only then – courts may look to its legislative history for evidence 

of congressional intent.”).

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emissions, even if reduced to near zero, would trigger the control measure 

requirement if vehicle miles traveled increased, for emissions would always be 

higher than if the number of vehicle miles traveled had remained constant. This

reading leads to the absurd result that transportation control measures or strategies 

will always be required if vehicle miles traveled increase, unless a vehicle fleet is 

100% electric and causes no tail-pipe emissions at all, no matter what the level of

vehicle miles traveled. The Court recognized that growth in vehicle miles traveled 

alone should not be viewed as automatically showing a “corresponding” growth in 

emissions, see 632 F.3d at 596, yet its interpretation does exactly that. The Court 

mentioned the “possibility” that “advances in clean car technology” would one day 

allow for increases in vehicle miles traveled without a “corresponding” increase in 

vehicle emissions, id., yet under the Court’s reading nothing short of a 100% 

electric fleet with zero tailpipe emissions would have that effect. 

EPA’s interpretation ensures that transportation control measures and 

strategies are adopted to offset any increase in vehicle miles traveled that causes an 

increase in actual aggregate vehicle emissions in the area. Such an increase would 

reflect an emissions “growth” in comparison to the actual levels of emissions in a 

previous year (a growth which might need to be remedied for an area to achieve its 

air quality goals), rather than simply a lesser rate of decrease of such emissions 

(which may not impair an area’s ability to meet air quality goals). The Court’s 

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ruling, instead, will force States and localities to offset any growth in vehicle miles 

traveled simply for its own sake, and devote scarce resources to address already 

declining motor vehicle emissions at the possible expense of other emissions 

sources whose pollution contribution may be in fact growing. 

Other legislative history cited by the Court, id. at 597, speaks only to 

offsetting growth in vehicle miles traveled, without reference to growth in 

emissions. That legislative history is thus unhelpful in interpreting the meaning of

“growth in emissions,” and directly disregards the statute’s direction that 

transportation control measures are needed to offset any “growth in emissions from 

growth in vehicle miles traveled.” 42 U.S.C. § 7511a(d)(1)(A) (emphasis added). 

Indeed, reliance on that legislative history conflicts with the Court’s own 

recognition that growth in emissions and growth in vehicle miles traveled are to be 

analyzed as separate questions. See 632 F.3d at 596. It was error for the Court to 

rely on legislative history to “bolster” its reading of what it declared to be an 

unambiguous statute, see id. at 2093, particularly because the legislative history 

fails to elucidate an interpretation that is both consistent with the language of the 

statute and workable as a practical matter. See BedRoc Ltd. v. United States, 541 

U.S. 176, 187 n.8 (2004) (courts “resort to legislative history only when necessary 

to interpret ambiguous statutory text”). 

The statutory provision is ambiguous on its face because it fails to specify 

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18

how EPA is to determine whether a “growth in emissions” will occur. It could be 

read the way the Court reads it – to require adoption of transportation control 

measures whenever vehicle emissions are higher than they would have been had 

vehicle miles traveled not increased – but it may equally be read (as EPA reads it) 

to require adoption of transportation control measures only when aggregate

vehicle emissions increase as a result of an increase in vehicle miles traveled. 

Under Chevron, the Court erred by failing to defer to EPA’s reasonable 

interpretation of the provision. 

CONCLUSION

For the reasons stated above, the Court should grant rehearing on the two 

issues raised herein.

 Respectfully submitted,

DATED: May 5, 2011

OF COUNSEL:

JEFFERSON L. WEHLING

Office of Regional Counsel

U.S. EPA Region IX

75 Hawthorne Street

San Francisco, CA 94105

JAN M. TIERNEY

MICHAEL W. THRIFT

Office of General Counsel

U.S. EPA

IGNACIA S. MORENO

Assistant Attorney General 

Environment & Natural Resources Div.

/s/ Austin D. Saylor . 

AUSTIN D. SAYLOR

United States Department of Justice

Environment & Natural Resources Div.

Environmental Defense Section

P.O. Box 23986

Washington D.C. 20026-3986

Tel: (202) 514-1880

Fax: (202) 514-8865

austin.saylor@usdoj.gov

Counsel for Respondent EPA

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19

Ariel Rios Building 

1200 Pennsylvania Avenue, N.W. 

Mail Code: 2344A 

Washington, DC 20460

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20

CERTIFICATE OF COMPLIANCE 

PURSUANT TO CIRCUIT RULE 40-1

I certify that pursuant to Circuit Rule 40-1, the attached petition for panel 

rehearing/petition for rehearing en banc is proportionally spaced, has a 14-point 

typeface, and contains 4,185 words, as counted by Microsoft Word, excluding the 

portions of the brief exempted by Fed. R. App. P. 32(a)(7)(B)(iii).

DATED: May 5, 2011 /s/ Austin D. Saylor . 

AUSTIN D. SAYLOR

United States Department of Justice

Environment & Natural Resources Div.

Environmental Defense Section

P.O. Box 23986

Washington D.C. 20026-3986

Tel: (202) 514-1880

Fax: (202) 514-8865

austin.saylor@usdoj.gov

Counsel for Respondent EPA

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21

CERTIFICATE OF SERVICE

I hereby certify that I electronically filed the foregoing PETITION FOR 

PANEL REHEARING with the Clerk of Court for the United States Court of 

Appeals for the Ninth Circuit by using the appellate CM/ECF system on May 5,

2011. 

I certify that all participants in the case are registered CM/ECF users and 

that service will be accomplished by the appellate CM/ECF system. 

/s/ Austin D. Saylor . 

AUSTIN D. SAYLOR

United States Department of Justice

Environment & Natural Resources Div.

Environmental Defense Section

P.O. Box 23986

Washington D.C. 20026-3986

Tel: (202) 514-1880

Fax: (202) 514-8865

austin.saylor@usdoj.gov

Counsel for Respondent EPA

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